TR6 Prime oil pump in rebuilt engine...

Hi,

I am getting the 6 motor rebuilt, and I forgot how I primed the oil pump with a drill last time. What do you all use to fit in the slot on top of the oil pump shaft?

Perry

I used a piece of threaded rod wit a slot cut into the end of it. Drill in reverse...

Cheers
Tush

+1. A slotted shaft made of anything that will fit run in reverse.

I am also in the habit (from the A-series world) of pulling the spark plugs and turning the engine over on the starter motor until pressure builds up.

Can't the plugs be left in, and just disconnect the ignition wire? Or does the compression lessen the priming effect?

KVH said:

Can't the plugs be left in, and just disconnect the ignition wire? Or does the compression lessen the priming effect?

Click to expand...

If you are spinning the engine over using the starter, then you remove the plugs to remove the load imposed by compression. If you are just spinning the oil pump, it doesn't matter whether you have the plugs in or not since the rest of the engine is stationary.

Good idea on spinning the engine. There is a flat on the rear cam journal that allows oil to reach the rocker shaft only once with every revolution of the cam. So, if the flat wasn't aligned with the oil passage, when priming the pump, no oil would go to the head.
Also, the lifter/cam lobe face is only oiled by splash/mist and won't receive any lubrication until the engine is running. So, it is very important to use lots of assembly lube on the cam.
I also found that the rod used to drive the oil pump should be a close fit in the dist. bushing or oil will tend to gush up around the rod.
Berry

I have done it both ways, using an electric drill and using the starter.
Beside the points already mentioned, the installation of the distributor drive gear after using the drill method can lead to a particular problem. I'm talking about aligning the drive gear with the oil pump.
I know of 3 cases where it was assumed there was alignment when the pedestal was installed. Because it was not, tightening the 2 nuts compressed the OP shaft down into the body of the pump.
The symptoms are no oil pressure when the cam is rotating..
My procedure now is to position the distributor drive gear, then from below insert the oil pump.
That way the rotation of the drive gear as it engages the cam teeth is removed from the process of aligning the drive gear with the oil pump.

Two questions:

What is meant by aligning the flat of the rear cam bearing?

Why doesn't Moss sell the leather washer to seal the oil pressure gauge so we know the readings are accurate?are the fittings different these days?

Maybe some one will post a picture...but in the meantime try to visualize this description from Haynes:
"Oil is fed to the valve gear via the hollow rocker shaft at reduced pressure by means of a scroll and 2 flats on the camshafts rear journal"
In other words its the flats and scroll that act as an oil pump when the cam is rotating that supplies lubrication to the rocker assembly, valve stems and guides and tappet bores.

The flat on the cam is used to restrict the flow of oil to the head. I guess the factory figured that without the restriction too much oil would flow to the head and starve the lower end. When you drive the oil pump without the engine running, it is a matter of chance as to whether the flat is in line with the oil gallery in block and allows oil to flow to the head. Think of the flats as a valve. If you don't see oil flowing around the rockers while driving the oil pump, try bumping the starter a few times until you see oil flow. Of course, this makes re-installing the dist. more difficult.
I don't think the leather washer is necessary with the new ss oil lines as they have a tapered seat. Leaving the washer out won't effect the gauge reading, but will cause a leak if not used with the original lines.
Berry

KVH said:

Why doesn't Moss sell the leather washer to seal the oil pressure gauge so we know the readings are accurate?are the fittings different these days?

Click to expand...

Others have answered your first question. As for the second... I don't think anyone sells the oil gauge washer but you would sure think someone would! I have heard of people using o-rings there but I believe that to be a bad choice since there is nothing to keep the o-ring from blowing "outward". What I have done recently is use heavy gasket paper to make fiber washers. They seem to work well enough. If you have a source for regular fiber washers I am sure they would work also. As for "new gauges", aftermarket gauges typically have 1/8 NPT threads so a little Teflon tape on the threads seals the joint.